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Full text of "The Cambridge Natural History"

CHAP.  XIV

SKELETON  OF SEAL

447

where, however, it is the
milk dentition that is
most pronounced, the
" permanent " being
feeble and very early
shed. Bufc the dentition
of the Pinnipedes pre-
sents other likenesses to
the Oetacea, "which are,
it must be remembered,
regarded by some as a
modification of the Carni-
vorous stock, in which
case, of course, the like-
nesses may be genetic
rather than due to
adaptation in the two
cases. There is a dis-
tinct tendency towards a
homodont series, the
grinding teeth being
often very simple, and
the very distinct carnas-
sial tooth of many terres-
trial Carnivores being
absent. Finally, the
number of the back teeth
shows some signs of being
on the increase; and
Professor Kukenthal has
found that this increase
is due to the division of
existing teeth. Here is
a point of likeness to the
many teeth of the typical
Toothed "Whales. Br.
Kehring found in several
examples of Halichoerus
grypus the normal five
back teeth increased to